/* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

/* TODO: check for overun of memory for names. */

#include	"mysys_priv.h"
#include	<m_string.h>
#include	<my_dir.h>	/* Structs used by my_dir,includes sys/types */
#include	"mysys_err.h"
#if defined(HAVE_DIRENT_H)
# include <dirent.h>
# define NAMLEN(dirent) strlen((dirent)->d_name)
#else
# define dirent direct
# define NAMLEN(dirent) (dirent)->d_namlen
# if defined(HAVE_SYS_NDIR_H)
#  include <sys/ndir.h>
# endif
# if defined(HAVE_SYS_DIR_H)
#  include <sys/dir.h>
# endif
# if defined(HAVE_NDIR_H)
#  include <ndir.h>
# endif
# if defined(_WIN32)
# ifdef __BORLANDC__
# include <dir.h>
# endif
# endif
#endif

#if defined(HAVE_READDIR_R)
#define READDIR(A,B,C) ((errno=readdir_r(A,B,&C)) != 0 || !C)
#else
#define READDIR(A,B,C) (!(C=readdir(A)))
#endif

/*
  We are assuming that directory we are reading is either has less than 
  100 files and so can be read in one initial chunk or has more than 1000
  files and so big increment are suitable.
*/
#define ENTRIES_START_SIZE (8192/sizeof(FILEINFO))
#define ENTRIES_INCREMENT  (65536/sizeof(FILEINFO))
#define NAMES_START_SIZE   32768


static int	comp_names(struct fileinfo *a,struct fileinfo *b);


	/* We need this because program don't know with malloc we used */

void my_dirend(MY_DIR *buffer)
{
  DBUG_ENTER("my_dirend");
  if (buffer)
  {
    delete_dynamic((DYNAMIC_ARRAY*)((char*)buffer + 
                                    ALIGN_SIZE(sizeof(MY_DIR))));
    free_root((MEM_ROOT*)((char*)buffer + ALIGN_SIZE(sizeof(MY_DIR)) + 
                          ALIGN_SIZE(sizeof(DYNAMIC_ARRAY))), MYF(0));
    my_free(buffer);
  }
  DBUG_VOID_RETURN;
} /* my_dirend */


	/* Compare in sort of filenames */

static int comp_names(struct fileinfo *a, struct fileinfo *b)
{
  return (strcmp(a->name,b->name));
} /* comp_names */


#if !defined(_WIN32)

MY_DIR	*my_dir(const char *path, myf MyFlags)
{
  char          *buffer;
  MY_DIR        *result= 0;
  FILEINFO      finfo;
  DYNAMIC_ARRAY *dir_entries_storage;
  MEM_ROOT      *names_storage;
  DIR		*dirp;
  struct dirent *dp;
  char		tmp_path[FN_REFLEN + 2], *tmp_file;
  char	dirent_tmp[sizeof(struct dirent)+_POSIX_PATH_MAX+1];

  DBUG_ENTER("my_dir");
  DBUG_PRINT("my",("path: '%s' MyFlags: %d",path,MyFlags));

#if !defined(HAVE_READDIR_R)
  mysql_mutex_lock(&THR_LOCK_open);
#endif

  dirp = opendir(directory_file_name(tmp_path,(char *) path));
#if defined(__amiga__)
  if ((dirp->dd_fd) < 0)			/* Directory doesn't exists */
    goto error;
#endif
  if (dirp == NULL || 
      ! (buffer= my_malloc(ALIGN_SIZE(sizeof(MY_DIR)) + 
                           ALIGN_SIZE(sizeof(DYNAMIC_ARRAY)) +
                           sizeof(MEM_ROOT), MyFlags)))
    goto error;

  dir_entries_storage= (DYNAMIC_ARRAY*)(buffer + ALIGN_SIZE(sizeof(MY_DIR))); 
  names_storage= (MEM_ROOT*)(buffer + ALIGN_SIZE(sizeof(MY_DIR)) +
                             ALIGN_SIZE(sizeof(DYNAMIC_ARRAY)));
  
  if (my_init_dynamic_array(dir_entries_storage, sizeof(FILEINFO),
                            ENTRIES_START_SIZE, ENTRIES_INCREMENT))
  {
    my_free(buffer);
    goto error;
  }
  init_alloc_root(names_storage, NAMES_START_SIZE, NAMES_START_SIZE);
  
  /* MY_DIR structure is allocated and completly initialized at this point */
  result= (MY_DIR*)buffer;

  tmp_file=strend(tmp_path);

  dp= (struct dirent*) dirent_tmp;
  
  while (!(READDIR(dirp,(struct dirent*) dirent_tmp,dp)))
  {
    if (!(finfo.name= strdup_root(names_storage, dp->d_name)))
      goto error;
    
    if (MyFlags & MY_WANT_STAT)
    {
      if (!(finfo.mystat= (MY_STAT*)alloc_root(names_storage, 
                                               sizeof(MY_STAT))))
        goto error;
      
      bzero(finfo.mystat, sizeof(MY_STAT));
      (void) strmov(tmp_file,dp->d_name);
      (void) my_stat(tmp_path, finfo.mystat, MyFlags);
      if (!(finfo.mystat->st_mode & MY_S_IREAD))
        continue;
    }
    else
      finfo.mystat= NULL;

    if (push_dynamic(dir_entries_storage, (uchar*)&finfo))
      goto error;
  }

  (void) closedir(dirp);
#if !defined(HAVE_READDIR_R)
  mysql_mutex_unlock(&THR_LOCK_open);
#endif
  result->dir_entry= (FILEINFO *)dir_entries_storage->buffer;
  result->number_off_files= dir_entries_storage->elements;
  
  if (!(MyFlags & MY_DONT_SORT))
    my_qsort((void *) result->dir_entry, result->number_off_files,
          sizeof(FILEINFO), (qsort_cmp) comp_names);
  DBUG_RETURN(result);

 error:
#if !defined(HAVE_READDIR_R)
  mysql_mutex_unlock(&THR_LOCK_open);
#endif
  my_errno=errno;
  if (dirp)
    (void) closedir(dirp);
  my_dirend(result);
  if (MyFlags & (MY_FAE | MY_WME))
    my_error(EE_DIR,MYF(ME_BELL+ME_WAITTANG),path,my_errno);
  DBUG_RETURN((MY_DIR *) NULL);
} /* my_dir */


/*
 * Convert from directory name to filename.
 * On UNIX, it's simple: just make sure there is a terminating /

 * Returns pointer to dst;
 */

char * directory_file_name (char * dst, const char *src)
{
  /* Process as Unix format: just remove test the final slash. */
  char *end;
  DBUG_ASSERT(strlen(src) < (FN_REFLEN + 1));

  if (src[0] == 0)
    src= (char*) ".";				/* Use empty as current */
  end= strnmov(dst, src, FN_REFLEN + 1);
  if (end[-1] != FN_LIBCHAR)
  {
    end[0]=FN_LIBCHAR;				/* Add last '/' */
    end[1]='\0';
  }
  return dst;
}

#else

/*
*****************************************************************************
** Read long filename using windows rutines
*****************************************************************************
*/

MY_DIR	*my_dir(const char *path, myf MyFlags)
{
  char          *buffer;
  MY_DIR        *result= 0;
  FILEINFO      finfo;
  DYNAMIC_ARRAY *dir_entries_storage;
  MEM_ROOT      *names_storage;
#ifdef __BORLANDC__
  struct ffblk       find;
#else
  struct _finddata_t find;
#endif
  ushort	mode;
  char		tmp_path[FN_REFLEN],*tmp_file,attrib;
#ifdef _WIN64
  __int64       handle;
#else
  long		handle;
#endif
  DBUG_ENTER("my_dir");
  DBUG_PRINT("my",("path: '%s' stat: %d  MyFlags: %d",path,MyFlags));

  /* Put LIB-CHAR as last path-character if not there */
  tmp_file=tmp_path;
  if (!*path)
    *tmp_file++ ='.';				/* From current dir */
  tmp_file= strnmov(tmp_file, path, FN_REFLEN-5);
  if (tmp_file[-1] == FN_DEVCHAR)
    *tmp_file++= '.';				/* From current dev-dir */
  if (tmp_file[-1] != FN_LIBCHAR)
    *tmp_file++ =FN_LIBCHAR;
  tmp_file[0]='*';				/* Windows needs this !??? */
  tmp_file[1]='.';
  tmp_file[2]='*';
  tmp_file[3]='\0';

  if (!(buffer= my_malloc(ALIGN_SIZE(sizeof(MY_DIR)) + 
                          ALIGN_SIZE(sizeof(DYNAMIC_ARRAY)) +
                          sizeof(MEM_ROOT), MyFlags)))
    goto error;

  dir_entries_storage= (DYNAMIC_ARRAY*)(buffer + ALIGN_SIZE(sizeof(MY_DIR))); 
  names_storage= (MEM_ROOT*)(buffer + ALIGN_SIZE(sizeof(MY_DIR)) +
                             ALIGN_SIZE(sizeof(DYNAMIC_ARRAY)));
  
  if (my_init_dynamic_array(dir_entries_storage, sizeof(FILEINFO),
                            ENTRIES_START_SIZE, ENTRIES_INCREMENT))
  {
    my_free(buffer);
    goto error;
  }
  init_alloc_root(names_storage, NAMES_START_SIZE, NAMES_START_SIZE);
  
  /* MY_DIR structure is allocated and completly initialized at this point */
  result= (MY_DIR*)buffer;

#ifdef __BORLANDC__
  if ((handle= findfirst(tmp_path,&find,0)) == -1L)
#else
  if ((handle=_findfirst(tmp_path,&find)) == -1L)
#endif
  {
    DBUG_PRINT("info", ("findfirst returned error, errno: %d", errno));
    if  (errno != EINVAL)
      goto error;
    /*
      Could not read the directory, no read access.
      Probably because by "chmod -r".
      continue and return zero files in dir
    */
  }
  else
  {

    do
    {
#ifdef __BORLANDC__
      attrib= find.ff_attrib;
#else
      attrib= find.attrib;
      /*
        Do not show hidden and system files which Windows sometimes create.
        Note. Because Borland's findfirst() is called with the third
        argument = 0 hidden/system files are excluded from the search.
      */
      if (attrib & (_A_HIDDEN | _A_SYSTEM))
        continue;
#endif
#ifdef __BORLANDC__
      if (!(finfo.name= strdup_root(names_storage, find.ff_name)))
        goto error;
#else
      if (!(finfo.name= strdup_root(names_storage, find.name)))
        goto error;
#endif
      if (MyFlags & MY_WANT_STAT)
      {
        if (!(finfo.mystat= (MY_STAT*)alloc_root(names_storage,
                                                 sizeof(MY_STAT))))
          goto error;

        bzero(finfo.mystat, sizeof(MY_STAT));
#ifdef __BORLANDC__
        finfo.mystat->st_size=find.ff_fsize;
#else
        finfo.mystat->st_size=find.size;
#endif
        mode= MY_S_IREAD;
        if (!(attrib & _A_RDONLY))
          mode|= MY_S_IWRITE;
        if (attrib & _A_SUBDIR)
          mode|= MY_S_IFDIR;
        finfo.mystat->st_mode= mode;
#ifdef __BORLANDC__
        finfo.mystat->st_mtime= ((uint32) find.ff_ftime);
#else
        finfo.mystat->st_mtime= ((uint32) find.time_write);
#endif
      }
      else
        finfo.mystat= NULL;

      if (push_dynamic(dir_entries_storage, (uchar*)&finfo))
        goto error;
    }
#ifdef __BORLANDC__
    while (findnext(&find) == 0);
#else
    while (_findnext(handle,&find) == 0);

    _findclose(handle);
#endif
  }

  result->dir_entry= (FILEINFO *)dir_entries_storage->buffer;
  result->number_off_files= dir_entries_storage->elements;

  if (!(MyFlags & MY_DONT_SORT))
    my_qsort((void *) result->dir_entry, result->number_off_files,
          sizeof(FILEINFO), (qsort_cmp) comp_names);
  DBUG_PRINT("exit", ("found %d files", result->number_off_files));
  DBUG_RETURN(result);
error:
  my_errno=errno;
#ifndef __BORLANDC__
  if (handle != -1)
      _findclose(handle);
#endif
  my_dirend(result);
  if (MyFlags & MY_FAE+MY_WME)
    my_error(EE_DIR,MYF(ME_BELL+ME_WAITTANG),path,errno);
  DBUG_RETURN((MY_DIR *) NULL);
} /* my_dir */

#endif /* _WIN32 */

/****************************************************************************
** File status
** Note that MY_STAT is assumed to be same as struct stat
****************************************************************************/ 


int my_fstat(File Filedes, MY_STAT *stat_area,
             myf MyFlags __attribute__((unused)))
{
  DBUG_ENTER("my_fstat");
  DBUG_PRINT("my",("fd: %d  MyFlags: %d", Filedes, MyFlags));
#ifdef _WIN32
  DBUG_RETURN(my_win_fstat(Filedes, stat_area));
#else
  DBUG_RETURN(fstat(Filedes, (struct stat *) stat_area));
#endif
}


MY_STAT *my_stat(const char *path, MY_STAT *stat_area, myf my_flags)
{
  int m_used;
  DBUG_ENTER("my_stat");
  DBUG_PRINT("my", ("path: '%s'  stat_area: 0x%lx  MyFlags: %d", path,
                    (long) stat_area, my_flags));

  if ((m_used= (stat_area == NULL)))
    if (!(stat_area= (MY_STAT *) my_malloc(sizeof(MY_STAT), my_flags)))
      goto error;
#ifndef _WIN32
    if (! stat((char *) path, (struct stat *) stat_area) )
      DBUG_RETURN(stat_area);
#else
    if (! my_win_stat(path, stat_area) )
      DBUG_RETURN(stat_area);
#endif
  DBUG_PRINT("error",("Got errno: %d from stat", errno));
  my_errno= errno;
  if (m_used)					/* Free if new area */
    my_free(stat_area);

error:
  if (my_flags & (MY_FAE+MY_WME))
  {
    my_error(EE_STAT, MYF(ME_BELL+ME_WAITTANG),path,my_errno);
    DBUG_RETURN((MY_STAT *) NULL);
  }
  DBUG_RETURN((MY_STAT *) NULL);
} /* my_stat */


#if defined(_MSC_VER) && (1==0)
/*
 * dlfcn-win32
 * Copyright (c) 2007 Ramiro Polla
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

//#include <windows.h>
//#include <stdio.h>

//#include "dlfcn.h"

/* Note:
 * MSDN says these functions are not thread-safe. We make no efforts to have
 * any kind of thread safety.
 */

typedef struct global_object {
    HMODULE hModule;
    struct global_object *previous;
    struct global_object *next;
} global_object;

static global_object first_object;

/* These functions implement a double linked list for the global objects. */
static global_object *global_search( HMODULE hModule )
{
    global_object *pobject;

    if( hModule == NULL )
        return NULL;

    for( pobject = &first_object; pobject ; pobject = pobject->next )
        if( pobject->hModule == hModule )
            return pobject;

    return NULL;
}

static void global_add( HMODULE hModule )
{
    global_object *pobject;
    global_object *nobject;

    if( hModule == NULL )
        return;

    pobject = global_search( hModule );

    /* Do not add object again if it's already on the list */
    if( pobject )
        return;

    for( pobject = &first_object; pobject->next ; pobject = pobject->next );

    nobject = malloc( sizeof(global_object) );

    /* Should this be enough to fail global_add, and therefore also fail
     * dlopen?
     */
    if( !nobject )
        return;

    pobject->next = nobject;
    nobject->next = NULL;
    nobject->previous = pobject;
    nobject->hModule = hModule;
}

static void global_rem( HMODULE hModule )
{
    global_object *pobject;

    if( hModule == NULL )
        return;

    pobject = global_search( hModule );

    if( !pobject )
        return;

    if( pobject->next )
        pobject->next->previous = pobject->previous;
    if( pobject->previous )
        pobject->previous->next = pobject->next;

    free( pobject );
}

/* POSIX says dlerror( ) doesn't have to be thread-safe, so we use one
 * static buffer.
 * MSDN says the buffer cannot be larger than 64K bytes, so we set it to
 * the limit.
 */
static char error_buffer[65535];
static char *current_error;

static int copy_string( char *dest, int dest_size, const char *src )
{
    int i = 0;

    /* gcc should optimize this out */
    if( !src && !dest )
        return 0;

    for( i = 0 ; i < dest_size-1 ; i++ )
    {
        if( !src[i] )
            break;
        else
            dest[i] = src[i];
    }
    dest[i] = '\0';

    return i;
}

static void save_err_str( const char *str )
{
    DWORD dwMessageId;
    DWORD pos;

    dwMessageId = GetLastError( );

    if( dwMessageId == 0 )
        return;

    /* Format error message to:
     * "<argument to function that failed>": <Windows localized error message>
     */
    pos  = copy_string( error_buffer,     sizeof(error_buffer),     "\"" );
    pos += copy_string( error_buffer+pos, sizeof(error_buffer)-pos, str );
    pos += copy_string( error_buffer+pos, sizeof(error_buffer)-pos, "\": " );
    pos += FormatMessage( FORMAT_MESSAGE_FROM_SYSTEM, NULL, dwMessageId,
                          MAKELANGID( LANG_NEUTRAL, SUBLANG_DEFAULT ),
                          error_buffer+pos, sizeof(error_buffer)-pos, NULL );

    if( pos > 1 )
    {
        /* POSIX says the string must not have trailing <newline> */
        if( error_buffer[pos-2] == '\r' && error_buffer[pos-1] == '\n' )
            error_buffer[pos-2] = '\0';
    }

    current_error = error_buffer;
}

static void save_err_ptr_str( const void *ptr )
{
    char ptr_buf[19]; /* 0x<pointer> up to 64 bits. */

    sprintf( ptr_buf, "0x%p", ptr );

    save_err_str( ptr_buf );
}

void *dlopen( const char *file, int mode )
{
    HMODULE hModule;
    UINT uMode;

    current_error = NULL;

    /* Do not let Windows display the critical-error-handler message box */
    uMode = SetErrorMode( SEM_FAILCRITICALERRORS );

    if( file == 0 )
    {
        /* POSIX says that if the value of file is 0, a handle on a global
         * symbol object must be provided. That object must be able to access
         * all symbols from the original program file, and any objects loaded
         * with the RTLD_GLOBAL flag.
         * The return value from GetModuleHandle( ) allows us to retrieve
         * symbols only from the original program file. For objects loaded with
         * the RTLD_GLOBAL flag, we create our own list later on.
         */
        hModule = GetModuleHandle( NULL );

        if( !hModule )
            save_err_ptr_str( file );
    }
    else
    {
        char lpFileName[MAX_PATH];
        int i;

        /* MSDN says backslashes *must* be used instead of forward slashes. */
        for( i = 0 ; i < sizeof(lpFileName)-1 ; i++ )
        {
            if( !file[i] )
                break;
            else if( file[i] == '/' )
                lpFileName[i] = '\\';
            else
                lpFileName[i] = file[i];
        }
        lpFileName[i] = '\0';

        /* POSIX says the search path is implementation-defined.
         * LOAD_WITH_ALTERED_SEARCH_PATH is used to make it behave more closely
         * to UNIX's search paths (start with system folders instead of current
         * folder).
         */
        hModule = LoadLibraryEx( (LPSTR) lpFileName, NULL, 
                                 LOAD_WITH_ALTERED_SEARCH_PATH );

        /* If the object was loaded with RTLD_GLOBAL, add it to list of global
         * objects, so that its symbols may be retrieved even if the handle for
         * the original program file is passed. POSIX says that if the same
         * file is specified in multiple invocations, and any of them are
         * RTLD_GLOBAL, even if any further invocations use RTLD_LOCAL, the
         * symbols will remain global.
         */
        if( !hModule )
            save_err_str( lpFileName );
        else if( (mode & RTLD_GLOBAL) )
            global_add( hModule );
    }

    /* Return to previous state of the error-mode bit flags. */
    SetErrorMode( uMode );

    return (void *) hModule;
}

int dlclose( void *handle )
{
    HMODULE hModule = (HMODULE) handle;
    BOOL ret;

    current_error = NULL;

    ret = FreeLibrary( hModule );

    /* If the object was loaded with RTLD_GLOBAL, remove it from list of global
     * objects.
     */
    if( ret )
        global_rem( hModule );
    else
        save_err_ptr_str( handle );

    /* dlclose's return value in inverted in relation to FreeLibrary's. */
    ret = !ret;

    return (int) ret;
}

void *dlsym( void *handle, const char *name )
{
    FARPROC symbol;

    current_error = NULL;

    symbol = GetProcAddress( handle, name );

    if( symbol == NULL )
    {
        HMODULE hModule;

        /* If the handle for the original program file is passed, also search
         * in all globally loaded objects.
         */

        hModule = GetModuleHandle( NULL );

        if( hModule == handle )
        {
            global_object *pobject;

            for( pobject = &first_object; pobject ; pobject = pobject->next )
            {
                if( pobject->hModule )
                {
                    symbol = GetProcAddress( pobject->hModule, name );
                    if( symbol != NULL )
                        break;
                }
            }
        }

        CloseHandle( hModule );
    }

    if( symbol == NULL )
        save_err_str( name );

    return (void*) symbol;
}

char *dlerror( void )
{
    char *error_pointer = current_error;

    /* POSIX says that invoking dlerror( ) a second time, immediately following
     * a prior invocation, shall result in NULL being returned.
     */
    current_error = NULL;

    return error_pointer;
}


#endif // _MSC_VER

